import {limitToRange} from '../lib/utils.js';
import {addMonths, addYears} from '../lib/date.js';

export function triggerDatepickerEvent(datepicker, type) {
  const detail = {
    date: datepicker.getDate(),
    viewDate: new Date(datepicker.picker.viewDate),
    viewId: datepicker.picker.currentView.id,
    datepicker,
  };
  datepicker.element.dispatchEvent(new CustomEvent(type, {detail}));
}

// direction: -1 (to previous), 1 (to next)
export function goToPrevOrNext(datepicker, direction) {
  const {minDate, maxDate} = datepicker.config;
  const {currentView, viewDate} = datepicker.picker;
  let newViewDate;
  switch (currentView.id) {
    case 0:
      newViewDate = addMonths(viewDate, direction);
      break;
    case 1:
      newViewDate = addYears(viewDate, direction);
      break;
    default:
      newViewDate = addYears(viewDate, direction * currentView.navStep);
  }
  newViewDate = limitToRange(newViewDate, minDate, maxDate);
  datepicker.picker.changeFocus(newViewDate).render();
}

export function switchView(datepicker) {
  const viewId = datepicker.picker.currentView.id;
  if (viewId === datepicker.config.maxView) {
    return;
  }
  datepicker.picker.changeView(viewId + 1).render();
}

export function unfocus(datepicker) {
  if (datepicker.config.updateOnBlur) {
    datepicker.update({autohide: true});
  } else {
    datepicker.refresh('input');
    datepicker.hide();
  }
}